Polyester Compositions Containing Metathesis Polymers with Reduced Recycle Color

Abstract

The present disclosure relates to aromatic polyester compositions, such as PET, comprising an unsaturated polymer prepared by metathesis polymerization having at least one or more specified terminal functional groups.

Description

This application claims the benefit of U.S. Provisional application No. 60/777,970, filed Mar. 1, 2006, and PCT Application No. PCT/US2007/005332, filed Mar. 1, 2007, which are incorporated herein by reference in their entirety.

FIELD OF THE INVENTION

This invention relates to aromatic polyester compositions that include unsaturated polymers prepared by metathesis polymerization.

BACKGROUND OF THE INVENTION

Polyester resins, such as poly(ethylene terephthalate) are commonly used to fabricate containers that are useful in food and beverage packaging. These resins, however, have limited packaging life, especially in the packaging of food and beverages that are sensitive to or degrade in the presence of oxygen.

To overcome these shortcomings, these resins have been blended or reacted with unsaturated polymers such as polybutadiene.

Unfortunately, the presence of these unsaturated polymers within the polyester composition leads to recycling difficulty. Namely, these compositions are not desirable for recycling because of the formation of color during the drying cycle. In particular, these compositions have suffered from the formation of red and yellow discoloration.

Inasmuch as use of these materials remains desirable, and the ability to recycle these materials is technologically important, there is a need to overcome problems associated with the formation of color within these materials.

SUMMARY OF THE INVENTION

In one or more embodiments, the present invention relates to a composition comprising the reaction product or a mixture of, (i) an aromatic polyester, and (ii) an unsaturated polymer having at least one terminal functional group, where said unsaturated polymer is formed by metathesis polymerization

In one or more embodiments, the present invention also relates to a composition comprising the reaction, product of, or a mixture of, (i) an aromatic polyester resin; and (ii) an unsaturated polymer having at least one terminal functional group, where said unsaturated polymer is formed by metathesis polymerization.

The terminal functional group that is usable herein is a group selected from hydroxyl, carboxylic acid, ester, carbonate, cyclic carbonate, anhydride, cyclic anhydride, lactone, amine, amide, lactam, cyclic ether, ether, aldehyde, thiazoline, oxazoline, phenol, melamine, and mixtures thereof. In one embodiment, the terminal functional group is a group selected from hydroxyl, carboxylic acid, and ester, and mixtures thereof.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

A. Introduction

One or more embodiments of this invention are directed to an aromatic polyester resin composition that includes an unsaturated metathesis polymer having at least one terminal functional group. In one or more embodiments, the unsaturated polymer is prepared by employing any metathesis reaction techniques. In one or more embodiments, the unsaturated metathesis polymer is characterized by pendant vinyl group content of less than about 2%. In these or other embodiments, the unsaturated metathesis polymer is characterized by having about 5 to about 25 double bonds per 100 carbon atoms in the polymer chain.

The terminal functional group that is usable herein is a group selected from hydroxyl, carboxylic acid, ester, carbonate, cyclic carbonate, anhydride, cyclic anhydride, lactone, amine, amide, lactam, cyclic ether, ether, aldehyde, thiazoline, oxazoline, phenol, melamine, and mixtures thereof. In one embodiment, the terminal functional group is a group selected from hydroxyl, carboxylic acid, and ester, and mixtures thereof.

B. Aromatic Polyester

1. Composition

In this invention, there may be used any aromatic polyester resin. In one or more embodiments, aromatic polyester resins derive from aromatic dicarboxylic acids and diols. Exemplary dicarboxylic acids include terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, diphenyl ether carboxylic acid, diphenyl dicarboxylic acid, diphenyl sulfone dicarboxylic acid, diphenoxyethanedicarboxylic acid, and mixtures thereof. In one or more embodiments, the polyesters may derive from derivatives of these acids such as dimethyl esters thereof. Exemplary diols include ethylene glycol, trimethylene glycol, tetramethylene glycol, neopentyl glycol, hexamethylene glycol, cyclohexanedimethanol, tricyclodecanedimethanol, 2,2-bis (4-hydroxy ethoxy phenyl) propane, 4,4′-bis (hydroxy ethoxy) diphenyl sulfone, diethylene glycol and mixtures thereof.

Examples of aromatic polyesters that may be employed in one or more embodiments include poly(alkylene terephthalate) resins such as poly(ethylene terephthalate), poly(butylene terephthalate), and poly(cyclohexane dimethylene terephthalate). Others include poly(alkylene naphthalate) resins such as poly(ethylene naphthalate), poly(butylene naphthalate), and poly(cyclohexane dimethylene naphthalate).

2. Characteristics

In one or more embodiments, the aromatic polyester resin may be characterized by an intrinsic viscosity that is in excess of 0.5 dl/g, in other embodiments in excess of 0.6 dl/g, and in other embodiments in excess of 0.7 dl/g, where the intrinsic viscosity is measured at 25° C. in a 50/50 blend of phenol and 1,1,2,2-tetrachloroethane. In these or other embodiments, the aromatic polyester resin may be characterized by an intrinsic viscosity that is less than 1.2 dl/g, in other embodiments less than 1.0 dl/g, and in other embodiments less than 0.95 dl/g.

In one or more embodiments, the aromatic polyester resin may be characterized by a melt temperature that is in excess of 200° C., in other embodiments in excess of 220° C., and in other embodiments in excess of 230° C.

3. Synthesis

In one or more embodiments, the aromatic polyester resins include those that are prepared from dimethyl terephthalate and ethylene glycol by a two-stage esterification process. Others include those prepared by direct esterification of a diacid with a diol or esterification of the diacid with ethylene oxide. Other methods for producing desirable resins for use in this invention are also known such as those methods described in U.S. Pat. No. 6,083,585, which is incorporated herein by reference.

C. Unsaturated Metathesis Polymer

1. General

The unsaturated polymers employed in the present invention are metathesis-synthesized polymers that have at least one or more terminal functional groups. In one or more embodiments, olefins such as cycloolefins and alpha, omega dienes, are polymerized by employing a metathesis catalyst to form the unsaturated polymer. The metathesis reaction may be ring opening metathesis polymerization (ROMP), acyclic diene metathesis polymerization (ADMET), or the like. In certain embodiments, metathesis-synthesized high molecular weight polymers are modified (e.g., molecular weight reduction) by employing metathesis catalysts to provide unsaturated polymers useful for practicing the present invention. A functional olefin (i.e., an olefin including one or more functional groups) is employed to yield unsaturated functional polymers or protected functional polymers. The unsaturated polymers comprise one or more functional groups. By employing metathesis polymerization techniques, the resulting polymer has from about 5 to about 25 double bonds per 100 carbon atoms in the polymer chain.

The terminal functional group that is usable herein is a group selected from hydroxyl, carboxylic acid, ester, carbonate, cyclic carbonate, anhydride, cyclic anhydride, lactone, amine, amide, lactam, cyclic ether, ether, aldehyde, thiazoline, oxazoline, phenol, melamine, and mixtures thereof. In one embodiment, the terminal functional group is a group selected from hydroxyl, carboxylic acid, and ester, and mixtures thereof.

2. Catalyst

Many metathesis catalysts are useful in practicing this invention. In one or more embodiments, the metathesis catalyst includes a transition metal carbene complex. Suitable transition metal carbene complexes include a positively charged metal center (e.g. in the +2, +4, or +6 oxidation state) that is penta- or hexa-coordinated. Exemplary transition metals include transition metals from Groups 3 to 12 of the Periodic Table, according to IUPAC conventions.

In one or more embodiments, the metathesis catalyst includes a ruthenium-based or osmium-based metathesis catalyst. Any ruthenium-based or osmium-based metathesis catalyst that is effective for metathesis polymerization reactions can be used. Advantageously, certain ruthenium and/or osmium-based catalysts are unaffected or only immaterially affected by the presence of certain advantageous functional groups present on the alkene.

In one embodiment, the ruthenium-based or osmium-based metathesis catalysts includes carbene complexes of the type sometimes referred to as Grubbs catalysts. Grubbs metathesis catalysts are described in U.S. Pat. Nos. 5,312,940, 5,342,909, 5,831,108, 5,969,170, 6,111,121, 6,211,391, 6,624,265, 6,696,597 and U.S. Published App. Nos. 2003/0181609 A1, 2003/0236427 A1, and 2004/0097745 A9, all of which are incorporated herein by reference.

Ru- or Os-based metathesis catalysts include compounds that can be represented by the formula

where M includes ruthenium or osmium, L and L′ each independently include any neutral electron donor ligand, A and A′ each independently include an anionic substituent, R³ and R⁴ independently comprise hydrogen or an organic group, and includes an integer from o to about 5, or where two or more of R³, R⁴, L, L′, A, and A′ combine to form a bidentate substituent.

In one embodiment, L and L′ independently include phosphine, sulfonated phosphine, phosphite, phosphinite, phosphonite, arsine, stibnite, ether, amine, amide, imine, sulfoxide, carboxyl, nitrosyl, pyridine, thioether, trizolidene, or imidazolidene groups, or L and L′ may together include a bidentate ligand. In one embodiment, L and/or L′ include an imidizolidene group that can be represented by the formulas

where R⁵ and R⁶ independently include alkyl, aryl, or substituted aryl. In one embodiment, R⁵ and R⁶ independently include substituted phenyls, and in another embodiment, R⁵ and R⁶ independently include mesityl. In one embodiment, R⁷ and R⁸ include alkyl or aryl, or form a cycloalkyl, and in another embodiment, are both hydrogen, t-butyl, or phenyl groups. Two or more of R⁵, R⁶, R⁷ and R⁸ can combine to form a cyclic moiety. Examples of imidazolidine ligands include 4,5-dihydro-imidazole-2-ylidene ligands.

In one embodiment, A and A′ independently include halogen, hydrogen, C₁-C₂₀ alkyl, aryl, C₁-C₂₀ alkoxide, aryloxide, C₂-C₂₀ alkoxycarbonyl, arylcarboxylate, C₁-C₂₀ carboxylate, arylsulfonyl, C₁-C₂₀ alkylsulfonyl, C₁-C₂₀ alkylsulfinyl, each ligand optionally being substituted with C₁-C₅ alkyl, halogen, C₁-C₅ alkoxy, or with a phenyl group that is optionally substituted with halogen, C₁-C₅ alkyl, or C₁-C₅ alkoxy, and A and A′ together may optionally include a bidentate ligand.

In one embodiment, R³ and R⁴ include groups independently selected from hydrogen, C₁-C₂₀ alkyl, aryl, C₁-C₂₀ carboxylate, C₁-C₂₀ alkoxy, aryloxy, C₁-C₂₀ alkoxycarbonyl, C₁-C₂₀ alkylthio, C₁-C₂₀ alkylsulfonyl and C₁-C₂₀ alkylsulfinyl, each of R³ and R⁴ optionally substituted with C₁-C₅ alkyl, halogen, C₁-C₅ alkoxy or with a phenyl group that is optionally substituted with halogen, C₁-C₅ alkyl, or C₁-C₅ alkoxy.

In one embodiment, L or L′ and A or A′ may combine to form one or more bidentate ligands. Examples of this type of complex are described as Class II catalysts in U.S. Pat. No. 6,696,597. In another embodiment, R³ or R⁴ and L or L′ or A or A′ may combine to form one or more bidentate ligands. This type of complex is sometimes referred to as Hoveyda or Hoveyda-Grubbs catalysts. Examples of bidentate ligands that can be formed by R³ or R⁴ and L or L′ include ortho-alkoxyphenylmethylene ligands.

Other useful catalysts include hexavalent carbene compounds including those represented by the formula

where M includes ruthenium or osmium, L, L′, L″ each independently include any neutral electron donor ligand, A, A′, and A″ each independently include an anionic substituent, and R³ and R⁴ independently comprise hydrogen or an organic group. In a manner similar to the penta-valent catalysts described above, one or more of the substituents in the hexa-valent complex may combine to form a bidentate substituent.

Examples of ruthenium-based carbene complexes include ruthenium, dichloro(phenylmethylene)bis(tricyclohexylphosphine), ruthenium, dichloro(phenylmethylene)bis(tricyclopentylphosphine), ruthenium, dichloro(3-methyl-2-butenylidene)bis(tricyclohexylphosphine), ruthenium, dichloro(3-methyl-2-butenylidene)bis(tricyclopentylphosphine), ruthenium, dichloro(3-phenyl-2-propenylidene)bis(tricyclohexylphosphine), ruthenium, dichloro(3-phenyl-2-propenylidene)bis(tricyclopentylphosphine), ruthenium, dichloro(ethoxymethylene)bis(tricyclohexylphosphine), ruthenium, dichloro(ethoxymethylene)bis(tricyclopentylphosphine), ruthenium, dichloro(t-butylvinylidene)bis(tricyclohexylphosphine), ruthenium, dichloro(t-butylvinylidene)bis(tricyclopentylphosphine), ruthenium, dichloro(phenylvinylidene)bis(tricyclohexylphosphine), ruthenium, dichloro(phenylvinylidene)bis(tricyclopentylphosphine), ruthenium,[2-(((2,6-bismethylethyl)-4-nitrophenyl)imino-kN)methyl-4-nitrophenolato-kO)]chloro-(phenylmethylene)(tricyclohexylphosphine), ruthenium,[2-(((2,6-bismethylethyl)-4-nitrophenyl)imino-kN)methyl-4-nitrophenolato-kO)]chloro-(phenylmethylene)(tricyclopentylphosphine), ruthenium,[2-(((2,6-bismethylethyl)-4-nitrophenyl)imino-kN)methyl-4-nitrophenolato-kO)]chloro-(3-methyl-2-butenylidene)(tricyclohexylphosphine), ruthenium,[2-(((2,6-bismethylethyl)-4-nitrophenyl)imino-kN)methyl-4-nitrophenolato-kO)]chloro-(3-methyl-2-butenylidene)(tricyclopentylphosphine), ruthenium,[1,3-bis-(2,4,6-trimethylphenyl)-2-imidazolidinylidene][2-(((2,6-bismethylethyl)-4-nitrophenyl)imino-kN)methyl-4-nitrophenolato-kO)]chloro-(phenylmethylene), ruthenium,[1,3-bis-(2,4,6-trimethylphenyl)-2-imidazolidinylidene][2-(((2,6-bismethylethyl)-4-nitrophenyl)imino-kN)methyl-4-nitrophenolato-kO)]chloro-(3-methyl-2-butenylidene), ruthenium, dichloro[1,3-dihydro-1,3-bis-(2,4,6-trimethylphenyl)-2H-imidazol-2-ylidene](phenylmethylene)(tricyclohexylphosphine), ruthenium, dichloro[1,3-dihydro-1,3-bis-(2,4,6-trimethylphenyl)-2H-imidazol-2-ylidene](phenylmethylene)(tricyclopentylphosphine), ruthenium, dichloro[1,3-dihydro-1,3-bis-(2,4,6-trimethylphenyl)-2H-imidazol-2-ylidene](3-methyl-2-butenylidene)(tricyclohexylphosphine), ruthenium, dichloro[l,3-dihydro-1,3-bis-(2,4,6-trimethylphenyl)-2H-imidazol-2-ylidene](3-methyl-2-butenylidene)(tricyclopentylphosphine), ruthenium, dichloro[1,3-dihydro-1,3-bis-(2,4,6-trimethylphenyl)-2H-imidazol-2-ylidene](3-phenyl-2-propenylidene)(tricyclohexylphosphine), ruthenium, dichloro[1,3-dihydro-1,3-bis-(2,4,6-trimethylphenyl)-2H-imidazol-2-ylidene](3-phenyl-2-propenylidene)(tricyclopentylphosphine), ruthenium, dichloro[1,3-dihydro-1,3-bis-(2,4,6-trimethylphenyl)-2H-imidazol-2-ylidene](ethoxymethylene)(tricyclohexylphosphine), ruthenium, dichloro[1,3-dihydro-1,3-bis-(2,4,6-trimethylphenyl)-2H-imidazol-2-ylidene](ethoxymethylene)(tricyclopentylphosphine), ruthenium, dichloro[1,3-dihydro-1,3-bis-(2,4,6-trimethylphenyl)-2H-imidazol-2-ylidene](t-butylvinylidene)(tricyclohexylphosphine), ruthenium, dichloro[1,3-dihydro-1,3-bis-(2,4,6-trimethylphenyl)-2H-imidazol-2-ylidene](t-butylvinylidene)(tricyclopentylphosphine), ruthenium, dichloro[1,3-dihydro-1,3-bis-(2,4,6-trimethylphenyl)-2H-imidazol-2-ylidene](phenylvinylidene)(tricyclohexylphosphine), ruthenium, dichloro[1,3-dihydro-1,3-bis-(2,4,6-trimethylphenyl)-2H-imidazol-2-ylidene](phenylvinylidene)(tricyclopentylphosphine), ruthenium,[1,3-bis-(2,4,6-trimethylphenyl)-2-imidazolidinylidene]-dichloro(phenylmethylene)(tricyclohexylphosphine), ruthenium,[1,3-bis-(2,4,6-trimethylphenyl)-2-imidazolidinylidene]-dichloro(phenylmethylene)(tricyclopentylphosphine), ruthenium,dichloro[1,3-bis-(2,4,6-trimethylphenyl)-2-imidazolidinylidene](3-methyl-2-butenylidene)(tricyclohexylphosphine), ruthenium,dichloro[1,3-bis-(2,4,6-trimethylphenyl)-2-imidazolidinylidene](3-methyl-2-butenylidene)(tricyclopentylphosphine), ruthenium,dichloro[1,3-bis-(2,4,6-trimethylphenyl)-2-imidazolidinylidene](3-phenyl-2-propylidene)(tricyclohexylphosphine), ruthenium,dichloro[1,3-bis-(2,4,6-trimethylphenyl)-2-imidazolidinylidene](3-phenyl-2-propylidene)(tricyclopentylphosphine), ruthenium,[1,3-bis-(2,4,6-trimethylphenyl)-2-imidazolidinylidene]-dichloro(ethoxymethylene)(tricyclohexylphosphine), ruthenium,[1,3-bis-(2,4,6-trimethylphenyl)-2-imidazolidinylidene]-dichloro(ethoxymethylene)(tricyclopentylphosphine), ruthenium,[1,3-bis-(2,4,6-trimethylphenyl)-2-imidazolidinylidene]-dichloro(t-butylvinylidene)(tricyclohexylphosphine), ruthenium,[1,3-bis-(2,4,6-trimethylphenyl)-2-imidazolidinylidene]-dichloro(t-butylvinylidene)(tricyclopentylphosphine), ruthenium,[1,3-bis-(2,4,6-trimethylphenyl)-2-imidazolidinylidene]-dichloro(phenylvinylidene)(tricyclohexylphosphine), and ruthenium,[1,3-bis-(2,4,6-trimethylphenyl)-2-imidazolidinylidene]-dichloro(phenylvinylidene)(tricyclopentylphosphine).

Commercially available Ru-based metathesis catalysts include ruthenium, dichloro(phenylmethylene)bis(tricyclohexylphosphine) (sometimes referred to as Grubbs First Generation Catalyst), ruthenium,[1,3-bis-(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(phenylmethylene) (tricyclohexylphosphine) (sometimes referred to as Grubbs Second Generation Catalyst), ruthenium, dichloro[[2-(1-methylethoxy)phenyl]methylene](tricyclohexylphosphine), (sometimes referred to as Hoveyda-Grubbs First Generation Catalyst), and ruthenium, [1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro[[2,(1-methylethoxy)phenyl] methylene], (sometimes referred to as Hoveyda-Grubbs Second Generation Catalyst). These Ru-based metathesis catalysts are available from Materia Inc. (Pasadena, Calif.).

In one embodiment, the Ru-based or Os-based metathesis catalyst can be prepared in situ. For example, a Ru or Os compound can be combined with an alkyne and an appropriate ligand under known conditions to form a metal carbene complex such as those described above.

Other metathesis catalysts that are also useful include tungsten and/or molybdenum-based metathesis catalysts. These catalysts include those that may be formed in situ from salts such as tungsten salts, and molybdenum and tungsten complexes known as Schrock's carbenes. Additionally, supported systems can be used, especially where gas-phase polymerization is employed. Tungsten-based metathesis catalysts are further described in U.S. Pat. Nos. 3,932,373, and 4,391,737, and Schrock catalysts are described in U.S. Pat. Nos. 4,681,956, 5,087,710, and 5,142,073, all of which are incorporated herein by reference.

3. Monomer

In one or more embodiments, useful olefin monomers include those that will undergo a metathesis reaction, i.e. those that include at least one metathesis-active double bond. The cycloolefins may be a cycloalkene or a cyclopolyene. Suitable examples of acyclic monomers include dienes, alpha omega dienes, oligomers of olefins, and the like.

In certain embodiments, the olefin includes a mixture of two or more different olefins that differ in at least one aspect such as the number of carbon atoms or heteroatoms and the amount and kind of substituents. Two or more different olefin monomers may also refer to two or more olefinic isomers. In one embodiment, the ratio of first olefin to second olefin is from about 99:1 to 1:99, in another embodiment from about 95:5 to 5:95, and yet another embodiment from about 90:10 to 10:90. In the instance where ROMP is used, the cycloolefin includes a mixture of two or more cycloolefins that differ in ring size or in substituents, or a mixture of two or more isomers of cycloolefins. Any combination of two or more cycloolefins can be used that provides the desired polymer properties, as discussed below. In one embodiment, the mixture includes cyclooctadiene and cyclopentene, or in other embodiments 1,5-cyclooctadiene and cyclooctene.

Any cycloolefin that can participate in a ring-opening metathesis polymerization (ROMP) reaction may be used. The cycloolefin may include one or more substituent groups and/or functional groups. The cycloolefin may be a cycloalkene or a cyclopolyene.

Cycloolefins include compounds represented by the formula

where z includes an integer from 1 to about 18. Examples of cycloolefins include cyclopropene, cyclobutene, benzocyclobutene, cyclopentene, dicyclopentadiene, norbornene, norbornadiene, cycloheptene, cyclooctene, 7-oxanorbornene, 7-oxanorbornadiene, cyclodecene, 1,3-cyclooctadiene, 1,5-cyclooctadiene, 1,3-cycloheptadiene, [2.2.1]bicycloheptenes, [2.2.2]bicyclooctenes, cyclohexenylnorbornenes, norbornene dicarboxylic anhydrides, cyclododecene, 1,5,9-cyclododecatriene, and derivatives thereof. It will be recognized by those of skill in the art that the thermodynamics of ring-opening polymerization varies based upon factors such as ring size and substituents. Ring-opening metathesis is described in K. J. Ivin and J. C. Mol, Olefin Metathesis and Metathesis Polymerization, Chap. 11 (1997), which is hereby incorporated by reference.

An alkene including a functional group must be present. The functional alkene, which may also be referred to as a functionalizing agent, includes at least one metathesis-active double bond. The acyclic alkene includes functional end-groups. The alkene may be represented by the formula

where Z includes a functional group and n includes an integer from 0 to about 20. A mixture of two or more functionalized alpha olefins may be used.

In one embodiment, the acyclic functional alkene can be represented by the formula

where each Z, which may be the same or different, is a functional group and n is an integer from o to about 20, in another embodiment, n is an integer from about 1 to about 9, in yet another embodiment, n is an integer less than about 6.

5. Synthesis

The synthetic techniques employed to prepare the unsaturated metathesis polymers having at least one or more terminal functional groups employed in the present invention include conventional metathesis polymerization techniques. These reactions may include ring-opening metathesis polymerization (ROMP) and/or acyclic diene metathesis polymerization (ADMET); these reactions are known in the art as set forth in U.S. Pat. Nos. 5,728,917 and 5,290,895, and 5,969,170, which are incorporated herein by reference. Metathesis polymers can also be prepared by the metathesis depolymerization of higher molecular weight unsaturated polymers (see WO2006/127483 A1). The use of functional alkenes, including multi-functional alkenes, in metathesis reaction, is also known as disclosed as U.S. Pat. No. 5,880,231 and U.S. Ser. No. 11/344,660, which are incorporated herein by reference.

In one or more embodiments, the reactants and catalysts are introduced in an inert atmosphere. The order of reactant or catalyst addition is not particularly limited. In one embodiment, the functional alkene and one or more metathesis-active olefins are combined to form a mixture, and then the metathesis catalyst is added to the mixture. One or more of the materials may be introduced together with a solvent. In other embodiments, the monomer or mixtures of monomers may first be polymerized followed by the addition of the functionalized alkene.

Metathesis polymerization reactions typically occur at temperatures that are below the ceiling temperature of one or more monomers. The ceiling temperature is the temperature above which polymerization does not occur to an appreciable extent. In one embodiment, the metathesis reaction occurs at a temperature of from minus 40° C. to about 100° C., in another embodiment, the temperature is from about minus 20° C. to about 75° C., in yet another embodiment, the temperature is from about 0° C. to about 55° C.

The progress of the reaction can optionally be monitored by standard analytical techniques, or by monitoring the percent solids. The metathesis reaction may optionally be terminated by adding a catalyst deactivator, such as ethyl vinyl ether.

After reaction, the metathesis-polymerized polymer may be isolated from the solvent using conventional procedures. In one or more embodiments, especially where the functional groups are sensitive to water, known techniques can be used to prevent or diminish contact with water.

Where a mixture of monomers is employed, the relative amount of each monomer is not particularly limited. In one embodiment, the ratio of first monomer to second monomer is from about 99:1 to about 1:99, in another embodiment, the ratio of first monomer to second monomer is from about 95:5 to about 5:95, in yet another embodiment, the ratio of first monomer to second monomer is from about 90:10 to about 10:90.

The amount of metathesis catalyst employed in the metathesis reaction is not critical, however a catalytic amount of catalyst is typically employed. In one embodiment, the amount of catalyst is at least about 0.1 mmol catalyst per 100 moles olefin, in other embodiments at least about 1 mmol catalyst per 100 moles olefin, in other embodiments, the amount of catalyst is from about 5 mmol to about 10 moles catalyst per 100 moles olefin, and still other embodiments from about 10 mmol to about 1 moles catalyst per 100 moles olefin, and yet another embodiment about 0.02 to about 0.5 moles catalyst per 100 moles olefin.

In other embodiments, metathesis catalysis can be employed in conjunction with existing high molecular weight metathesis polymers to form the desired polymers of this invention. In other words, metathesis catalysis can be employed to prepare polymer of a desired molecular weight by introducing the catalyst to high molecular weight polymer and alkene. The high molecular weight polymer that can be used in this process includes high molecular weight polymer produced by metathesis polymerization. For example, high molecular weight polymer resulting from the polymerization of cyclooctene having a molecular weight of about 90 kg/mole, less than 1% pendant vinyl groups, and about 12-15 double bonds per 100 carbon atoms in the polymer chain are commercially available under the tradename Vestenamer™ (Degussa). These polymers can be contacted with a metathesis catalyst and an alkene to produce a lower molecular weight metathesis polymer. Also, by employing functionalized alkenes, the resulting metathesis polymer can be functionalized. Optionally, a cycloolefin or diene containing a metathesis-reactive double bond can be added to copolymerize with the base polymer and thereby form an interpolymer.

6. Characteristics of Unsaturated Polymer

a. Pendant Vinyl Group Content

In one or more embodiments, the unsaturated metathesis polymer having at least one or more terminal functional groups employed in the present invention may be characterized by a relatively low pendant vinyl group content. Pendant vinyl group refers to an alkenyl group along the polymer backbone with one point of attachment to the backbone exclusive of a terminal end group. In one or more embodiments, the polymer may include less than about 2%, in other embodiments less than about 1%, in other embodiments less than about 0.5%, and in other embodiments less than about 0.05% of vinyl groups or 1,2 configuration. In one or more embodiments, the unsaturated polymer is substantially devoid of pendant vinyl units where substantially devoid includes that amount or less pendant vinyl units that would otherwise have an appreciable impact on the polymer and/or blend of the invention. In one or more embodiments, the unsaturated polymer is devoid of pendant vinyl groups.

b. Glass Transition Temperature (T_g)

In one or more embodiments, the T_g of the unsaturated metathesis polymer having at least one or more terminal functional groups may be less than about 0° C., in other embodiments less than about minus 10° C., and in yet other embodiments less than about minus 15° C. In still another embodiment, the T_g may be from about minus 15 to about minus 115° C.

c. Melting Temperature (T_m)

In one or more embodiments, the melting point of the unsaturated polymer having at least one or more terminal functional groups may be from about minus (−) 40° C. to about (+) 50° C., in other embodiments from about minus 35° C. to about 40° C., and in yet other embodiments from about minus 30° C. to about 20° C.

In certain embodiments, where the polymer backbone is synthesized from two or more different monomers, the melting point of the polymer can be controlled by selecting the relative amounts of monomers. For example, the melting point of a copolymer prepared from cyclooctadiene and cyclopentene may vary from about minus (−) 30° C. to about (+) 40° C. as the mole fraction of pentene units in the copolymer decrease from about 0.3 to about zero percent, based upon the total moles of cyclooctadiene and cyclopentene.

d. Number Average Molecular Weight (M_n)

In one or more embodiments, the unsaturated polymer having at least one or more terminal functional groups may be characterized by a number average molecular weight (M_n) of at least about 0.5 kg/mole, in other embodiments at least about 1 kg/mole, in other embodiments at least about 1.5 kg/mole, and in other embodiments at least about 2.0 kg/mole. In one or more embodiments, the unsaturated polymer may be characterized by a number average molecular weight of less than about 100 kg/mole, in other embodiments less than about 80 kg/mole, in other embodiments less than about 60 kg/mole, and in other embodiments less than 40 kg/mole and in another embodiment, less than about 20 kg/mole. In one or more embodiments, the unsaturated polymer may be characterized by a molecular weight distribution (Mw/Mn) of from about 1.05 to about 2.5, in other embodiments from about 1.1 to about 2.0, and in other embodiments from about 1.2 to about 1.8. Molecular weight may be determined by using standard GPC techniques with polystyrene standards.

f. Double Bond Content

In one or more embodiments, the methathesis polymer having at least one or more terminal functional groups may be characterized by relatively low unsaturation. In one or more embodiments, the metathesis polymer contains from about 5 to about 25 double bonds per 100 carbon atoms, in other embodiments, the metathesis polymer contains from about 6 to about 20 double bonds per 100 carbon atoms, in other embodiments from about 7 to about 18 double bonds per 100 carbon atoms, and in other embodiments, the metathesis polymer contains from about 10 to about 15 double bonds per 100 carbon atoms in the polymer.

g. Microstructure

The metathesis polymers herein have a cis content of about greater than 10%; and in another embodiment, greater than 30%, and in another embodiment, greater than 50%.

D. Blending/Reacting Polymer and PET

1. General

In one or more embodiments of this invention, the compositions can be prepared by mixing or blending of an aromatic polyester resin and the metathesis polymer having at least one or more terminal functional groups herein. Techniques for mixing are known in the art, and this invention is not limited to the selection of a particular method. In one embodiment, the mixing occurs in a reactive extruder such as a twin-screw extruder.

2. Conditions

The mixing or blending of the aromatic polyester resin and the metathesis polymer having at least one or more terminal functional groups can occur over a wide range of conditions. These conditions are selected such that substantially all of the functional groups attached to the metathesis polymer will be expected to react with the poly(ethylene terephthalate). In one or more embodiments, the mixing or blending can occur at a temperature of from about 230° C. to about 310° C. and in other embodiments from about 250° C. to about 290° C.

3. Residence Time

In one or more embodiments, the residence time within the extruder is maintained for about 2 to about 6 minutes, and in other embodiments from about 3 to about 5 minutes.

4. Other Ingredients

In one or more embodiments, the aromatic polyester resin and metathesis polymer having at least one or more terminal functional groups may be mixed or blended in the presence of catalysts, modifiers, heat stabilizers, antioxidants, colorants, crystallization nucleating agents, fillers, biodegradation accelerants or additional constituents that can be incorporated into the composition. In general, aromatic polyester compositions are known as described in U.S. Pat. No. 6,083,585, which is incorporated herein by reference.

In one or more embodiments, the aromatic polyester composition may include a transition metal catalyst.

In one or more embodiments, the aromatic polyester compositions of this invention include from about 0.05 to about 0.15 weight percent transition metal catalyst based upon the weight of the metathesis polymer. In other embodiments, the composition includes from about 0.07 to about 0.12 weight percent, and in other embodiments from about 0.09 to about 0.11 weight percent based upon the weight of the metathesis polymer.

In one or more embodiments, the aromatic polyester compositions may include or be modified by condensation branching or coupling agents that alter the intrinsic viscosity of the compositions. In other words, the compositions include the reaction product between the branching agent and the aromatic polyester and/or metathesis polymer having at least one or more terminal functional groups. These agents may include polycondensate branching agents. In one or more embodiments, these branching agents may include trimellitic anhydride, aliphatic dianhydrides and aromatic dianhydrides. In one embodiment, pyromellitic dianhydride (i.e., benzene 1,2,4,5-tetracarboxylicacid dianhydrides) is employed.

Numerous factors can alter the amount of branching agent that may be desirable, or alter whether the use of a branching agent may be desired. In one or more embodiments, the composition of this invention includes or is modified by from about 0.01 to about 0.15 weight percent branching agent based upon the weight of the metathesis polymer. In other embodiments, the composition includes from about 0.05 to about 0.12 weight percent, and in other embodiments from about 0.09 to about 0.11 weight percent branching agent based upon the weight of the metathesis polymer having at least one or more terminal functional groups herein.

5. Amounts

a. Concentrate

In one or more embodiments of this invention, the composition including the aromatic polyester resin and metathesis polymer having at least one or more terminal functional groups herein are prepared as concentrates or masterbatches that can be subsequently added to other thermoformable resins (e.g., aromatic polyester resins) for use in preparing particular articles. In forming these concentrates, which are often in the form of pellets, the composition of this invention may include at least 1%, in other embodiments at least 5%, and in other embodiments at least 10% by weight unsaturated metathesis polymer having at least one or more terminal functional groups herein based upon the total weight of the total composition. In these or other embodiments, these concentrates or masterbatch pellets include less than 30%, and in other embodiments less than 20%, and in other embodiments less than 15% by weight metathesis polymer based upon the total weight of the composition.

b. Thermoformable Composition

In one or more embodiments of this invention, particularly where the composition is employed in thermoforming process (as opposed to the manufacture of concentrate or masterbatch pellets), the compositions include at least 0.05%, in other embodiments at least 0.5%, and in other embodiments at least 0.9% by weight metathesis polymer based upon the total weight of the composition. In these or other embodiments, the thermoformable composition includes less than 5%, in other embodiments less than 3%, and in other embodiments less than 1.5% by weight based upon the total weight of the composition.

In one or more embodiments, the composition of the invention includes the reaction product between an aromatic polyester resin and a metathesis polymer having at least one or more terminal functional groups herein.

E. Morphology

In one or more embodiments, the compositions of this invention include an aromatic polyester resin matrix having dispersed therein domains of the metathesis polymer. As those skilled in the art appreciate, the characteristics, especially the size, of these metathesis polymer domains can be adjusted based upon mixing conditions and functionality of the metathesis polymer. It is expected that in one or more embodiments, the metathesis polymer domains are characterized by an expected average diameter of less than 400 nanometers, in other embodiments less than an expected 300 nanometers, and in other embodiments less than an expected 200 nanometers. The size and stability of the domains formed are expected to be controlled and stabilized by the reaction and attachment of the functional metathesis polymer to the aromatic polyester.

F. Uses

In one or more embodiments, the compositions of this invention are advantageously thermoformable, and therefore they can be used in the various thermoforming techniques that are known such as, but not limited to, injection molding, blow molding, and compression molding. In one or more embodiments, the compositions of this invention can also be extruded.

In one or more embodiments, the compositions can be used to fabricate packaging walls and packaging articles. In certain embodiments, these packaging articles include those used with perishable foods and beverages.

In one particular use, the compositions of this invention can be used to fabricate bottles. In other embodiments, the compositions can be used in the manufacture of packaging films.

G. Advantages

The compositions of one or more embodiments of this invention are advantageously recyclable where formation of color is reduced. A further advantage would be expected by the reaction and attachment of the functional metathesis polymer to the aromatic polyester substantially reducing the leaching or migration of the rubber polymer away from the polyester.

In order to demonstrate the practice of the present invention, the following examples have been prepared and tested. The examples should not, however, be viewed as limiting the scope of the invention. The claims will serve to define the invention.

EXAMPLE 1

Synthesis of Low Molecular Weight, Telechelic Acetate-Terminated Polypentenamer

A batch mixture comprised of 1.51 kg nitrogen-purged cyclopentene and 0.087 kg of 1,4-diacetoxy-2-butene were charged into a 1-gallon volume reactor, heated to 25° C., and stirred. A solution of 0.4 g of Grubbs' 2^nd generation metathesis catalyst [Aldrich] in 100 mL dry, degassed toluene (0.45 mmol, 50,000:1 olefin:Ru) was charged into the vessel. Within 25 minutes, polymerization of the monomer began to occur, and a reaction temperature increase to 78° C. was observed. The resulting cement was then stirred at a constant 40° C. temperature for an additional 1 hour. At this time, a solution of 5 mL ethyl vinyl ether in 50 mL toluene was added to the polymer solution and stirred at 40° C. in order to deactivate any residual metathesis catalyst. The resulting polymer had the following characteristics: M_n=6.3 kg/mol; M_w/M_n=1.8; trans olefin content=78%; vinyl olefin content=0%; >95% acetate terminated end groups.

Hvdrolysis of Ester End Groups to Hydroxyl End Groups in Polypentenamer

A solution of 250 g acetate-terminated polypentenamer prepared above dissolved in 1.5 L toluene was stirred and chilled to 0° C. in an ice bath. Approximately 500 mL of a 0.5 M sodium methoxide in methanol solution was added to the polymer solution and stirred for 4 hours at 0° C. At this time, the polymer solution was poured into a flask containing 1 L of a 0.5 M methanolic HCl solution and stirred for 30 minutes. The resulting mixture was placed in a separatory funnel and two layers were allowed to separate. The lower wet methanol layer was removed and the polymer was extracted with 1 L of DI water aliquots until the pH of the solution was neutral. Any emulsions formed were broken up by addition of saturated NaCl solution. After extraction, the polymer solution was dried using anhydrous magnesium sulfate and the solvent was removed under reduced pressure. ¹H NMR analysis indicated that 98% of the acetate end groups were hydrolyzed to hydroxyl groups.

The resultant hydroxyl terminated polypentenamer is expected to be useful in preparing compositions with aromatic polyesters.

EXAMPLE 2

Synthesis of Telechelic, Low Molecular Weight Cyclooctene-1,5-Cyclooctadiene Copolymer

In a 1-gallon volume stainless steel reactor, a batch mixture was charged consisting of 1185 mL (996 g, 9.0 mol) of degassed cyclooctene, 560 mL (497 g, 4.6 mol) degassed 1,5-cyclooctadiene, and 60 mL (65.5 g, 0.38 mol) degassed cis-1,4-diacetoxy-2-butene. The mixture was stirred and heated to 50° C. A solution of 0.42 g (0.50 mmol) Grubbs' 2^nd generation ruthenium metathesis catalyst in 10 mL dry, degassed toluene was prepared under inert atmosphere and added to the monomer mixture. Withing 1 minute, an increase in reaction temperature began to occur, with the peak temperature reaching 114° C. within 15 minutes. The reaction was stirred for 2 hours, after which a solution of 10 mL ethyl vinyl ether in hexanes was added to deactivate the metathesis catalyst. After stirring for 30 minutes, the polymer was dropped into bottles for storage and analyzed. The product polymer was an amber colored oily liquid. The resulting material had the following characteristics: M_n=9.2 kg/mol; M_w/M_n=1.82; 67/33 trans/cis olefin content; 48/52 mole ratio octenyl/butenyl units.

EXAMPLE 3

Depolymerization of High Molecular Weight Polyoctenamer to Low Molecular Weight, Telechelic Cyclooctene-1,5-Cyclooctadiene Copolymer

In a 1-gallon volume stainless steel reactor, 830 g of polyoctenamer (Degussa Vestenamer 8012) pellets (Mn=65 kg/mol; Mw/Mn=1.8; 100% octenyl unit compositioni), 470 mL (417 g, 3.85 mol)degassed 1,5-cyclooctadiene, 40 mL (43.4 g, 0.25 mol) of degassed cis-1,4-diacetoxy-2-butene, and 700 mL of degassed hexanes were charged. The heterogeneous mixture was stirred and heated to 57° C. in order to melt the solid Vestenamer polymer. A solution of 0.22 g (0.26 mmol) Grubbs' 2^nd generation ruthenium catalyst in 10 mL dry, degassed toluene was prepared under an inert atmosphere and added to the contents of the reactor. The reaction was stirred for 2 hours at a constant 57° C. temperature. After this period, a solution of 5 mL ethyl vinyl ether in 100 mL hexanes was added to deactivate the metathesis catalyst. After stirring for 30 minutes, the polymer was dropped into bottles for storage and analyzed. The product polymer was an amber colored oily liquid. The resulting material had the following characteristics: Mn=7.4 kg/mol; Mw/Mn=2.09; 48/52 mole ratio octenyl/butenyl units.

As with the polymer of Example 1, the terminal functionalized polymers of Examples 2 and 3 are expected to be useful in preparing compositions with aromatic polyesters.

Various modifications and alterations that do not depart from the scope and spirit of this invention will become apparent to those skilled in the art. This invention is not to be duly limited to the illustrative embodiments set forth herein.

Claims

1. A composition comprising:

(i) an aromatic polyester; and

(ii) an unsaturated polymer formed by metathesis polymerization, having at least one or more terminal functional groups selected from the group consisting of hydroxyl, carboxylic acid, ester, carbonate, cyclic carbonate, anhydride, cyclic anhydride, lactone, amine, amide, lactam, cyclic ether, ether, aldehyde, thiazoline, oxazoline, phenol, melamine groups, and mixtures thereof.

2. The composition of claim 1, wherein said aromatic polyester comprises a poly(alkylene terephthalate) resin.

3. The composition of claim 2, wherein said poly(alkylene terephthalate) resin is selected from the group consisting of poly(ethylene terephthalate), poly(butylene terephthalate), mixtures thereof, and interpolymers thereof.

4. The composition of claim 1, wherein the unsaturated metathesis polymer comprises from about 5 to about 25 double bonds per 100 carbon atoms in the polymer.

5. The composition of claim 1, wherein the terminal functional group is selected from the group consisting of hydroxyl, ester, and carboxylic acid groups, and mixtures thereof.

6. The composition of claim 1, comprising at least about 0.5% by weight unsaturated metathesis polymer based upon the total weight of the unsaturated metathesis polymer and the aromatic polyester resin.

7. The composition of claim 1, wherein said unsaturated metathesis polymer has less than about 2% pendant vinyl groups.

8. The composition of claim 1, further comprising a cobalt compound.

9. A reaction product comprising:

(i) an aromatic polyester; and

(ii) an unsaturated polymer formed by metathesis polymerization having at least one or more terminal functional groups selected from the group consisting of hydroxyl, carboxylic acid, ester, carbonate, cyclic carbonate, anhydride, cyclic anhydride, lactone, amine, amide, lactam, cyclic ether, ether, aldehyde, thiazoline, oxazoline, phenol, melamine groups, and mixtures thereof.

10. The composition of claim 9, wherein said aromatic polyester comprises a poly(alkylene terephthalate) resin.

11. The composition of claim 10, wherein said poly(alkylene terephthalate) resin is selected from the group consisting of a poly(ethylene terephthalate), poly(butylene terephthalate), mixtures thereof, and interpolymers thereof.

12. The composition of claim 9, wherein said unsaturated metathesis polymer comprises less than about 2% pendant vinyl groups.

13. The composition of claim 9, wherein the unsaturated metathesis polymer comprises from about 5 to about 25 double bonds per 100 carbon atoms in the polymer.

14. The composition of claim 9, wherein the terminal functional group is selected from the group consisting of hydroxyl, ester and carboxylic acid groups, and mixtures thereof.

15. The composition of claim 9, wherein said aromatic polyester and said unsaturated metathesis polymer are covalently bonded to each other by an ester linkage.

16. The composition of claim 9 comprising at least about 0.5% by weight unsaturated metathesis polymer based upon the total weight of the unsaturated metathesis polymer and the aromatic polyester resin.

17. The composition of claim 9, further comprising a cobalt compound.

18. The composition of claim 10, further comprising a coupling agent.

19. The composition of claim 1, wherein said unsaturated metathesis polymer has a number average molecular weight (Mn) of from about 1 to about 100 kg/mol.